Method of manufacturing wire cord



Dec. 11, 1951 M. A. CROSB/Y ETAL METHOD OF MANUFACTURING WIRE CORD 2SHEETS-SHEET 1 Original Filed March 8, 1943 INVENTORS MELVIN A CROSBY BYENRIQUE L.LUAGES n joulmum Joul/nwl ATTORNEYS Dec. 11, 1951 CROSBY ETAL2,577,843

METHOD OF MANUFACTURING WIRE CORD Original Filed March 8, 1945 2SHEETS-SHEET 2 INVENTORS MELVIN A. CROSBY BY ENRIQUE L. LUACES ATTORNEYSbased Dec. 11,1951

METHOD OF MANUFACTURING WIRE CORD Melvin A. Crosby and Enrique L.Luaces, Dayton,

Ohio, assignors to The Dayton Rubber Company, a corporation of OhioOriginal applications March 8, 1943, Serial No. 478,428, and December14, 1946, Serial No. 716,348. Divided and this application December 14,1946, Serial No. 716,347

1 This invention relates to the manufacture of V-belts, and moreparticularly deals with a method whereby belts reinforced with wire maybe manufactured.

This application is a division of our copending applications, SerialNumber 478,428, filed March 8, 1943, now abandoned; and Serial No.716,348,

' filed December 14, 1946, now Patent No. 2,500,523.

In the past V-belts have been made generally with a neutral axis sectioncomprising a plurality of cords of cotton or similar textile material'ofporous or absorbent nature laid parallel to each other and along thelongitudinal axis of the belt.

More recently, efiorts have been made in substituting fine metal wire,for the textile cords, but since the wire is nonjporous andnon-absorbent, great diificulty has/been experienced in ob taining afirm bond between the wire and the rubber composition of which the beltbody is made.

The adhesiveness of the rubber composition to the wire increases as thediameter of the wire decreases, but since the strength of the wiredecreases as its diameter decreases, it is not feasible to reduce thediameter of the wire as much as might be necessary to obtain the bestpossible bond between the wire and the rubber composi-- tion.

In order to increase the adhesion between the wire and the rubbercomposition the wire is frequently subjected to electrochemical orelectrolytical treatment. For example, steel wire may be plated withcopper and the adhesion between the wire and the rubber thus increasedbecause the thin copper plate on the wire appears to react chemicallywith sulfur or sulfur compounds in the rubber composition and thereby toform a chemico-mechanical bond between the wire and the rubbercomposition forming the body of the belt. While this procedure issatisfactory and improves greatly the bond between the wire and therubber composition, it presents certain inconveniences and is, in asense, impractical because the wire must be utilized in the manufactureof belts shortly after it has been plated as otherwise passivation takesplace and the advantageous action between the copper plate and thesulfur or sulfur compounds in the rubber composition diminishes rapidlyand ultimately becomes negligible.

The primary purpose of the present invention is to provide means wherebythe adhesion between metal wire used in place of textile cord and therubber composition forming the body of the belt 1 Claim. (01. 154-91)being manufactured may be increased by means which does not possess theundesirable characteristics and disadvantages which have just beenmentioned with respect to electroplated wire.

According to the present invention, fine steel wire (0.004 to 0.005 inchdiameter) is coated with rubber composition by dipping or otherwise andthen formed into a cable thus providing a cable in which each strand ofwire is covered by a film of rubber composition which provides a firmmechanical bond between the several strands forming the cable andbetween the cable and rubber composition in which it may be embedded.

In one other form of the present invention fine steel wire may be placedover a thin layer of rubber composition, covered with a second thinlayer of rubber composition, and the resulting sandwich in which thewire is the meat is rolled around the longitudinal axis of said wires.In this form of the invention the several strands of wire are coveredwith film of rubber composition and as the assembly is rolled up, theseveral rubber coated strands unite with each other to form a unitarybodywhich may be employed in place of cords particularly in the largersizes.

The nature of the present invention will be better understood from thefollowing description taken in connection with the annexed drawings inwhich: I

Fig. 1 is a view showing the manner in which fine wire may be placedover a thin layer of rubber composition and covered with a second thinlayer of rubber composition to form a sandwich";

Fig. 2 illustrates the manner in which the sandwich of Fig. 1 is rolledto form a cord of our invention;

Fig. 3 illustrates the manner in which a plurality of strands of finewire may be coated with rubber composition and then twisted to form acable;

Fig. 4 is a view taken along line 4-4 of Fig. 3 and illustrates themanner in which the individual strands of wire are covered with athinfilm of rubber composition and united to each other by a web ofrubber composition;

Fig. 5 illustrates in perspective and partly in cross section the cablewhich results from the cabling operation illustrated in Fig. 3;

Fig. 6 is a perspective view partly in cross section showing the articlewhich results when bunched fine wires are immersed in rubber compositionto produce an uncabled wire cord;

Fig. '7 is a perspective view partly in cross section showing the mannerin which the wire cords 3 Fig. 5 or Fig. 8 or Fig. 11 may be employed inbuilding a wrapped type v-belt;

Fig. 8 illustrates the manner in which the wire cord of Fig. 5 or-Fig. 6or Fig. 11 may be employedinthebuildingotaraw-edgetypeoi v-belt;

Fig. 9 illustrates the manner in which the belt o!Fig.7orFig.8maybeusedinasinglebelt drive;

Fig. 10 illustrates the manner in which the belt of Fig. 7 or Fig. 8 maybe employed in multi-belt drive; and

Fig. 11 is a perspective view partly in crosssection showing the cordresulting from the operations illustrated in Figs. 1 and 2.

Referring now to the drawings in detail, in Fig. 1 the numeral is atable top or other similar smoothsuriace on which there is deposited athin film of rubber composition 2 I. Thercover there are placed aplurality of spaced strands of fine wire 22 which are covered by a toplayer of rubber composition 22. In Fig. 2 there is illustrated themanner in which the laminated article of Fig. 1 is rolled around thelongitudinal axis of said wires to form a plurality of involute layers.

Reierring now to Fig. 3, the numeral 2 represents strands of fine wirewhich are dipped in a solution 25 held in a vessel 2.. The solution 25may consist, for example, of rubber composition dissolved in a suitablesolvent. As the strands leave the bath 25 coated with a thin film o!rubber composition they are passed through a hotbox 21 wherein thesolvent is evaporated substantially completely so that the rubbercovered strands of wire leaving the box 21 are substantially dry butremain somewhat tacky and adhesive with respect to each other. Therubber covered strands, as they leave the hotbox 21, will appear asshown in Fig. 4 and will comprise a plurality of wire strands 28 coveredwith a thin film oi rubber composition 22 and held together by a web ofrubber composition II. The rubber covered strands of wire are twisted toform a cord as illustrated in Fig. 3 at Ii. The cable It produced asshown in Fig. 3 is illustrated in an enlarged manner in Fig. 5.

While in Fig. 3 the several strands of wire are shown entering the bathside by side and substantially equidistantly spaced, this procedure neednot be followed exactly although it does provide certain benefits fromthe point of view of uniformity of the cable ultimately obtained. Forexample, a plurality of strands of fine wire may be bunched and dippedin the rubber composition. The rubber eovered article thus obtained isillustrated in Fig. 6 and consists of a plurality of wire strands l2embedded in and covered with rubber composition It.

Depending on the diameter and number orwireswhichareusedtoiormthewirecordoi Fig. 5 or Fig. 6, these cords maybe used directly or they may be employed in the manufacture of cables ofgreater diameter either by twisting together several such cords or bybraiding them to term a cable of larger diameter. The diameter of thecord obtained according to the method illustrated in Fig. 1 and Fig. 2will depend on the width of the laminated sheet which is rolled to formthe cord, the diameter 0! the final article depending on the length ofthe sheet which is rolled to form it. Likewise. the cord resulting fromthe method illustrated in Figs. 1 and 2 maybeuseddirectlyasacordormaybeunitedwith other similar cords either bytwisting into a cable or by braiding to form a cable of larger diameter.

The belt illustrated in Fig. 'I'consists of a wrapper 24, a tensionsection II, a neutral axis section It including a plurality of wirecords I1 and a compression section 22, while the belt illustrated inFig. 8 comprises a plurality 01 layers of rubberized iabric ll iormingthe tension section, a neutral axis section 40 including a plurality ofwire cords ,a compression section 42 and a covering 42 or rubberizedfabric on its underside. The former is known as a wrapped belt while thelatter is known as a raw edge belt. They are illustrated as havingsmooth top and bottom surraces, but the wire cords oi the presentinvention may be utilized in making wrapped belts and raw edge beltshaving cogs on the underside or on the top or on both the top andundersides.

In Fig. 9 there is illustrated the manner in which a single belt 44 maybe utilized for driving coniointlypulleys 45 and ll, and in Fig. 10there is illustrated the manner in which pulleys 41 and 42 may be drivenby a plurality or V-belts 49. The single belt 44 and the multiple belts49 could be otthe type illustrated in Fig. 7 and in Fig. 8. y In themaking of the wire cords illustrated in Figs. 2, 5 and 6, it will benoted. the rubber composition not only thoroughly covers the severalstrands of wire. but also provides a complete outer cover for the cord.When'the rubber composition hardens by vulcanization in the course 0!the curing or vulcanizing oi the belt in which the cords are used, therubber composition securely anchors the several strands of fine wire andholds them together in a permanent and strong bond thus forming aunitary article, and since the outer surface of the cord consists ofrubber composition, this outer covering likewise hardens byvulcanization and forms an integral structure with the other sections ofthe belt. I! the wire cables of Figs. 2, 5 and 8 are further cabled bytwisting or by braiding to form cables of greater diameter and greaterstrength, the same conditions exist and in the ultimate an integralstructure is obtained.

Belts provided with wire cords such as described and illustrated in thepresent application are substantially better in service than similarbelts in the manufacture of which the orthodox textile cord has beenemployed. Since the elasticity of metal is less than that 01 cotton, for

example, belts made with wire cord such as the wire cord of the presentinvention will resist stretch to a greater extent and will thus provemore satisfactory because they will cause less slippage and will thustransmit more power. Tests indicate that belts having wire cords give aservice life from four to seven times greater than belts oi theidentical design in which the orthodox type of cotton cords has beenused.

It will be understood that while we have illustrated and describedcertain embodiments of our invention, it is not our intention to haveour invention limited to or circumscribed by the specific details ofconstruction, arrangement of parts, materials, procedures or proportionsmentioned or illustrated in view oi the fact that our invention issusceptible to modifications according to individual conditions andpreference without departing from the spirit of this disclosure and thescope o! the appended claim.

We claim:

second thin layer of rubber composition; and rolling the resultinglaminated body around the 1011- gitudinal axis of said wires in aplurality of lnvolute layers to form a cord.

MELVIN A. CROSBY.

E. L. LUACES.

REFERENCES CITED UNITED STATES PATENTS Name Date Dew July 18,1918

Number Number Number 17,359 or 1928 Name- Date Swinehart Dec. 5, 1922Grabau Dec. 23, 1924 Castricum June 30,1925 Hauvette Jan. 10,1939Conradson June 15,1943 Sulofl Aug. 12,1947

FOREIGN PATENTS Country Date Australia Oct. 22,1929

